Subtract 18/42 from 1/5
1/5 - 18/42 is -8/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 5 × 42 = 210,
1/5 = 1 × 42/5 × 42 = 42/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
18/42 = 18 × 5/42 × 5 = 90/210 - Subtract the two like fractions:
42/210 - 90/210 = 42 - 90/210 = -48/210 - After reducing the fraction, the answer is -8/35
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